Not sure on the prefix-length because I'm wanting .48.0 through .63.0 advertised to both ISPs with 50.0/23 and 52.0/23 being prepended so ISP2 is preferred. So my thought was in mine the first line caught it all with the next two restricting it. Otherwise I would have accept lines prepending or not subnetting to accommodate the prepends I want.
Terri On Dec 27, 2013, at 3:45 PM, Keith Barber wrote: > Those will only announce just those 3 subnets. > If you have smaller subnets that you're advertising, you can use the > 'prefix-length' field. > > Adjust the length depending on how large or small your advertisements are. > > > /routing filter > add action=accept chain=isp1-out prefix=192.168.50.0/23 set-bgp-prepend=5 > add action=accept chain=isp1-out prefix=192.168.52.0/23 set-bgp-prepend=5 > add action=accept chain=isp1-out prefix=192.168.48.0/20 prefix-length=20-23 > add chain=isp1-out action=discard > > -Keith- > > > > ----- Original Message ----- > From: "Terri Kelley" <[email protected]> > To: "Mikrotik discussions" <[email protected]> > Sent: Friday, December 27, 2013 5:25:12 PM > Subject: [Mikrotik] bgp prepend > > Been too long since I've done any of this and haven't in RouterOS. I'm > wanting to load balance incoming traffic to my bgp edge from two fiber > connections. So my thought was to prepend the subnets of my /20 that I want > to come in from the other upstream, say ISP2. ISP1 is always heavier use. > Seems in cisco that you could advertise the whole /20 and then just put the > couple of prepended subnets that you wanted rather than having to break down > all of it. Is that correct? If that is the case it would look something like > this in RouterOS… > > /routing filter > add action=accept chain=isp1-out prefix=192.168.48.0/20 > add action=accept chain=isp1-out prefix=192.168.50.0/23 set-bgp-prepend=5 > add action=accept chain=isp1-out prefix=192.168.52.0/23 set-bgp-prepend=5 > add chain=isp1-out action=discard > add action=accept chain=isp2-out prefix=192.168.48.0/20 > add chain=isp2-out discard > > That should put the 50.0/23 and 52.0/23 over on isp2 and allow everything > else to choose which side. Or do I have to list all of the subnets prepended > and not? > > Terri Kelley > Network Engineer > 254-697-6710 > Farm to Market Broadband > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://mail.butchevans.com/pipermail/mikrotik/attachments/20131227/b9084a4b/attachment.html> > _______________________________________________ > Mikrotik mailing list > [email protected] > http://mail.butchevans.com/mailman/listinfo/mikrotik > > Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS > _______________________________________________ > Mikrotik mailing list > [email protected] > http://mail.butchevans.com/mailman/listinfo/mikrotik > > Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.butchevans.com/pipermail/mikrotik/attachments/20131227/e0e3ea2c/attachment.html> _______________________________________________ Mikrotik mailing list [email protected] http://mail.butchevans.com/mailman/listinfo/mikrotik Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
